Methods of and apparatus for selectively producing fluids from a plurality of subsurface fluid zones



Dec. 24, 1963v ROwN C. C. B METHODS OF AND APPARATUS FOR SELECTIVELYPRODUCING FLUIDS FROM A PLURALITY 0F' SUBSURFACE FLUID ZONES Filed April27, 1959 2 Sheets-Sheet l l'. J E /A 1. l i ii vf. X P5 n un :jx-:1 I

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'd [IMG/JIA! jfam ATTORNEYS Dec. 24, 1963 c. c. BRowN 3,115,187

METHODS oF AND APPARATUS FOR SELECTIVELY PRonucING FLuIns FROM APLURALITY OF SUBSURFACE FLUID ZONES Filed April 2'7, 1959 2 Sheets-Sheet2 FHMPPAHEAV//K N., 5 M mm .n C -UNA 000 W United States Patent 8Claims. (Cl. 166-Z24) This invention relates to new and usefulimprovements in methods of and apparatus for selectively producingtluids from a plurality of subsurface iiuid zones.

It is not unusual for a well bore to traverse a plurality of well uidproducing formations or zones, and in recent years multiple zoneproduction methods and apparatus have come into general use to permitthe fluid production from each zone to be produced without comminglingwith the production from the other zones. The usual multiple Zoneproduction apparatus has ordinarily involved the use of spaced packersfor separating the zones and an independent tubing string for conductingthe iiow from each zone. lf the bore traverses two zones, two tubingstrings have been provided and similarly three Zones have required threestrings, four Zones have required four strings and so on. However, it isreadily apparent that costs limit the number of independent stringswhich can be economically employed and further the physical size of thewell bore is a restricting factor as to how many separate tubing stringscan be actually disposed therein.

Furthermore, where a well bore traverses a plurality of zones, as forexample, four, ve or six in number, it is unlikely that all of the zonesare equal in productivity; as a matter of fact, it is more usual thatone, two or possibly more are relatively weak zones and would not ofthemselves justify the cost and expense of running a separate tubingstring to communicate with such weaker zone. For this reason, it hasbeen the practice to shut off, as by cementing, the less productivezones and to complete the well without reference to said lesserproductive zone or lt is one object of this invention to provide animproved method and apparatus which will permit the selectiveprovduction of well iluids from any number of producing formationstraversed by a single well bore without the necessity of employing aseparate or independent tubing string for each producing zone. Thisinvention constitutes an improvement upon the invention disclosed in mycopending application Serial No. 729,172, tiled April 17, 1958, nowPatent No. 3,059,699.

An important object is to provide an improved method which involvesdisposing at least dual tubing strings and 4the required number ofpackers for separating the producing zones, within the well bore,landing said strings and packers in iinal position before setting thepackers, then subsequently setting said packers, and finally selectivelyestablishing communication between each tubing string and one of theproducing zones, whereby each tubing conducts fluids from one of thezones to the surface; the method permitting the initially selected zonesto be produced and further permitting a change to be made at any time toshut of new from the initially selected zones and allow iiow from otherzones into said strings.

Another object is to provide an improved well apparatus having at leasta pair of tubing strings provided with the required number of wellpackers to separate a plurality of producing zones traversed by a wellbore, together with Valve means mounted in each string between eachpacker and manipulatable from the surface to selectively establishcommunication between each tubing string and one of the producing Zones.

A further object is to provide an apparatus, of the character described,wherein the valve means which con- "ice trols communication between eachtubing string and the producing zones is operated by wire line or cablelowered within said tubing, whereby the selective opening and closing ofsaid valve means does not disturb the well packers which are in setposition.

Still another object is to provide an apparatus, of the characterdescribed, having a pair of tubing strings for separately producing fromtwo of the zones traversed by the well bore but which lends itself toconversion to a triple production apparatus, in which event the wellcasing in which the apparatus is disposed functions as the thirdproduction string.

The construction designed to carry out the invention will be hereinafterdescribed, together with other features thereof.

The invention will be more readily understood from a reading of thefollowing speciiication and by reference to the accompanying drawingsforming a part thereof, wherein an example of the invention is shown,and wherein:

FlGURE 1 is a schematic View illustrating the first tubing string, thewell packers and associate parts being lowered into the well bore;

FIGURE 2 is a similar view showing the packers and tiret string inposition and illustrating the second tubing string being lowered;

FlGURl-E 3 is a similar view with both tubing strings and all wellpackers in final position with the packers set and showing the valveslocated in accordance with the present invention between the wellpackers;

FTGURE 4 is a vertical sectional view of one of the valves and alsoshowing the sleeve shifting tool which shifts the valve in a downwarddirection;

FIGURE 5 is a view similar to FIGURE 4 but showing the sleeve shiftingtool which shifts the valve in an upward direction;

FIGURE 6 is a View similar to FIGURE 3 and illustrating a cross-overunit which is shown in dotted lines, within the first tubing string,whereby the casing annulus may be employed as a ow conductor;

FTGURE 7 is a transverse sectional view showing the cross-over device inmore detail, and

FIGURE 8 is a transverse sectional View of a closure unit which closesthe bypass openings which coact with a cross-over unit.

ln the drawings .the letter W designates a well bore which traverses aplurality of fluid producing Zones. The usual well casing l@ extendsthroughout the length of the bore and is suitably perforated at lilaopposite each of the producing zones whereby fluid from said zones mayiiow into ythe casing. Five producing Zones or formations Fil, F2, F3,F4 and Fe are illustrated but, of course, the number of formationstraversed by `any particular well bore is depen-dent upon the particularsubsurface conditions. The producing Zones are spaced from each otherand it is desirable that production from each zone be independent of theother zones. lt is also desirable to selectively produce from the zonesbecause one formation may be stronger than 4another or its productionlife may be longer or shorter than other Zones. The present inventionhas to do with selectively producing from the various production zonesthrough a minimum number of tubing strings.

in carrying out the present invention, a lirst tubing string T has aplurality of packers mounted thereon. The number of packers will, ofcourse, depend upon the nurnber of producing zones to be separated andin the present instance live such packers fare shown. The packers aredesignated P1, P2, P3, P4 and P5 and are properly spaced on the rsttubing string T whereby when in linal position. said packers will bedisposed between the producing formations or Zones. The first tubingstring, together with the packers thereon, is lowered to the positionshown in FTGURE 2 which properly locates the packers.

For the sake of convenience the lower portion of the second tubingstring T2 is made in sections which connect the packers (FIGURES l and2) The section 'T2- connects packers P2 `and P3 while section "f2-2connects packers P3 and P4 and the additional section TZ-S connectspackers P4 and P5. The upper section 'T2-d of the second tubing stringcomprises the main part of the second tubing string T2 and is adapted tobe independently handled and run separately which facilitates locatingboth tubing strings in position within the well bore.

The packers P1 to P5 are preferably hydraulically actuated packers ofthe type shown in my co-pending application Serial Number 525,585, filedAugust 1, 1955, now Patent No. 2,953,066. With this type of packer, bothtubing strings and the packers may be located in nal position lwith thewell head equipment A in place prior to the time that the packers areset. This makes it possible to circulate through and around the packersand perform any other operation within the well bore prior to moving thepackers into set posit-ion.

Following setting of the packers as shown in FIGURE 3, said packersfunction to separate the fluid production of the various formations Flthrough F from each other. The lower end of the first tubing string Tlcommunicates with the area below the lowermost packer Pd and, therefore,communicates with the lowerrnost producing zone or formation F1. Thelower end of the second tubing string T2 communicates with the producingzone or formation F2 which is ybetween packers P1 and P2. Normally wheredual strings are used, each string conducts the flow from one formationto the surface and thus where only two tubing strings are employed, ithas heretofore been possible to produce only two Zones. When one of saidzones becomes depleted, then the dual installation, in effect, becomes asingle producing well.

In order to make possible the production of several formations on aselective basis, a plurality of control valves are .mounted in thetubing strings. Control valve lll is connected in tubing string Tl inthat portion of the tubing between packers P2 and P3. A similar valvelll is connected in that section of the second string T2 between thesame packers. Similarly, valves lla and lilla are located betweenpackers P3 and P4 and communicate with formation F4; additional valvesMb and llllb are disposed between packers P4 and P5 and communicate withformation F5. As will be explained, the valves are operable from thesunface and may be selectively opened and closed to establishcommunication between each tubing string `and the desired formation.

Although the structure of the valves ll to Zlib and 111 to lllb issubject to variation, one type of valve, which has been foundparticularly adaptable for the present purpose, is illustrated inFIGURES 4 and 5. This valve includes an outer body d2 having radialinlet openings i3. A sleeve member i4 having radial slots or openings l5is slidable axially lwithin the body or housing. When the valve memberis in lowered position (FIGURE 4), the openings 13 and ll5 are out ofregistration and the valve is closed. Shifting of the valve to a raisedposition (FlG- URE 5) moves openings i3 and llS into registrationwhereby the valve is open yand a flow into the tubing string may occur.

Each valve is adapted to be actuated by a sleeve shifting tool 16 whichis lowerable through the tubing string on a wire line or cable ll. Theparticular shifting tool forms no part of the present invention and maybe one such as is available on the open market and manufactured by theGarrett Oil Tools Company of Longview, Texas. The shifting tool hasdownwardly facing dogs 1S which engage the upper end of the sleeve ld sothat a downward jar will shift the sleeve to a lowered position. Thetool is also provided with upwardly facing dogs i9 which are adapted toengage the lower end of the sleeve to move the same upwardtly. Theparticular valve shifting tool and its operan tion are illustrated in myprior ctv-pending application serial No. 729,172,61ed April 17, s.

The tubing strings Ti and T2 are lowered into the well bore in themanner heretofore described and as shown in FIGURES l to 3. The valvesll to 1lb and lll to lllb are in a closed position. As has been noted,the lower ends of the strings Ti and TZ are normally open so that afterthe packers have been moved to set position (FIGURE 3), production fromthe zones or formations Fl and F2 may occur. A

So long as Zones Fil and F2 are producing, the various valves in thestrings Tl and T2 remain in closed positioni However, assuming thatformation Fil becomes depleted and normal flow stops, then it isdesirable to produce one of the other zones F3, F4 or F5 through the rststring Tl. ln such event a suitable closure or plug 2@ (FIGURE 3) ispumped downwardly through the string Tl and engages a seat 21 providedat the lower end of the string. This closes downward dow of fluidthrough the string T1.

Thereafter, the sleeve shifting tool 16 having the up` wardly facingdogs 19 is lowered downwardly and, as= suming that ow from formation F3is to be directed into tubing Tl, the shifting tool is engaged with thevalve member lid of valve 1l. Upon an upward pull after the dogs 19 haveengaged the lower end of the sleeve 14, said sleeve is shifted upwardlyto move ports 13 and l5 into registration and thereby establishcommunication between formation F3 and tubing Tl. The valve shifting'tool l5 is so constructed that after the sleeve 14 has moved to itsupper position, the dogs 19 are retracted tov permit removal ofthe tool.Thereafter, production from zone F3 is through the first tubing stringTll. It is, of course, obvious that if desired either valve lla or 11bcould be actuated to establish communication' between formations F4 orF5 as the case may be, instead of pro; ducing from formation F3.

If the formation F2 with which the second tubing string T2 communicatesis depleted first, then the plug Zt) is pumped downwardly through tubingT2 and engages a seat 22 provided at the lower end of said tubing.Thereafter, the sleeve shifting tool le is utilized to open one of thevalves lill, lila or 1Mb to establish communicad tion with the secondtubing'string TZ. Thus the operator has a choice and may select theparticular formation which is to be produced after the initial formationbed comes depleted. The invention contemplates the selecVd tive openingand closing of the various valves and actually one formation may beproduced for a length of time after which its valve may be closed andanother valve opened. This renders the apparatus extremely versatile andallows selective production from a great many zones with only two tubingstrings. Although it is desirable to use a minimum number of tubingstrings, conditions may' sometimes warrant the use of three strings oftubing with a plurality of packers. ln such case, the valves would belocated between the packers in all three strings so that selectiveproduction from any particular zone to any par ticular string may beaccomplished.

The usual manner of producing from three Zones or formationssimultaneously involves the use of three tubing strings. However, undercertain conditions it is possible to quickly convert the presentapparatus from a dual production arrangement to triple productionapparatus. This can be accomplished by utilizing the upper portion ofthe well casing lil, which is above the upper packer P5 as a flowconductor and such a modification is illustrated in FIGURES 6 to 8. Inthis modication a plurality of ports 2S are formed in the tubing stringT1 at a point below the upper packer P5. Similar ports 26 are alsoformed in the string Tl and are located above said packer. The ports 25establish communication with the area between packers Pr and P5 wherebyflow from this area may enter the tubing Tl; similarly ports 26establish communication between the tubing string and the annulus whichis, of course, the casing 10.

In order to utilize the upper portion of the casing as a third lowconductor, a removable cross-over assembly 2'7 is arranged to be loweredand removably latched within the tubing is illustrated in FIGURE 7. Thisassembly includes a main body 28 having well known latches 29 engageablewithin an annular recess 30 provided in the string T1. When the body isin position, an elongate passage 3i has its lower end communicating withthe ports 25 in the tubing string while its upper end is incommunication with the bore of the string above the body. Suitablepacking elements 32 seal off between the body and the bore of the tubingso that flow from the area below packer P enters passage 31 and isdirected upwardly through the tubing Tll. A second passage 33 in thebody conducts ilow from the bore of the tubing T1 below the body andupwardly to the ports 26 whereby this tluid is conducted upwardlythrough the casing it). Thus, by disposing the cross-over assembly 27within the tubing T ll to coact with the ports 25 and 26, a thirdpassage or conductor for well uids to the surface is obtained.

lf the cross-over arrangement is not desired, the assembly 2'7 isremoved and a closure unit 34 shown in FTGURE 8 is substituted therefor.This unit includes a body 35 having latch members 36 engageable in therecess 30 to latch said unit in position. Suitable sealing rings 32a,which properly seal off the ports 25 and 26, are mounted on the exteriorof the body. The body is formed with an axial bore 37 so that upwardflow through the tubing T1 occurs through the unit 34 and then passesupwardly through said string. With the closure unit in place, ports 25and 26 are closed and normal upward flow through the tubing may takeplace.

In both forms of the apparatus, selective production from a plurality ofzones is possible. Any two zones may be produced through the two tubingstrings merely by manipulating the proper valve or valves. At any timethat a formation becomes depleted, it is only necessary to open one ofthe valves communicating with another formation and production cancontinue. Although it is ordinarily not desirable to commingle uids fromtwo different zones, conditions might occur which would allow suchcommingling and in such instance, by proper manipulation of the valves,the fluids from more than one zone can be conducted to the surfacethrough a single tubing string.

By employing the packers, such as hydraulicallyactuated packers, whichmay be set without any longitudinal movement of the tubing strings, thetubing strings may be landed in iinal position, the well head equipmentA may be connected after which any washing or circulating operation maybe carried out before the packers are moved into final set position. Theuse of the sleeve type valves, which are shiftable by means of a wireline tool, provides for selective control of the valves whilemaintaining the well under full control.

The foregoing disclosure and description of the invention isillustrative and explanatory thereof and various changes in the size,shape and materials, as well as in the details of the illustratedconstruction, may be made within the scope of the appended claimswithout departing from the spirit of the invention.

What I claim is:

1. An apparatus for selectively producing uids from a plurality of uidproducing zones including, a pair of 'parallel tubing strings extendingdownwardly within the well bore, a plurality of well packers on saidstrings and positioned between the producing zones when the tubingstrings are in the well bore, whereby setting of the well packersseparates said producing zones, nonremovable valve means mounted in eachtubing string located between the packers for controlling communicationbetween each tubing string and each producing zone, and means controlledfrom the surface for actuating the valve means to selectivelycommunicate each tubing string with a desired fluid producing zone.

2, An apparatus for selectively producing fluids from a plurality offluid producing zones including, a pair of parallel tubing stringsextending downwardly within the well bore, a plurality of well packerson said strings and positioned between the producing zones when thetubing strings are in the well bore, whereby setting of the well packersseparates said producing zones, each tubing string having openingstherein which are disposed between the well packers, each openingcommunicating with one of the producing zones which is sealed olf by thepackers above and below such opening, and nonremovable valve meansmounted within the tubing string associated with each opening wherebyflow through said openings may be selectively controlled by theactuation of said valve means.

3. An apparatus as set forth in claim 2, together with an actuator forthe valve means lowerable on a wire line within said tubing strings,whereby the operation of said valve means is controlled from the surfaceof the well.

4. A well apparatus including, a rst tubing string, a second tubingstring, a plurality of well packers mounted on said strings in spacedrelationship and adapted to separate various producing Zones traversedby a well bore, the iirst tubing string having its lower endcommunicating with the lowerrnost zone below the lowerrnost packer, saidirst string also having radial openings therein with each radial openingbeing located between the packers so that each opening is incommunication with one of the producing Zones, non-removable valve meansmounted in said rst tubing string and associated with each opening forcontrolling ow therethrough, said second string having its lower end incommunication with the zone immediately above the lowermost packer andalso having radial openings therein with each radial opening beinglocated between the packers so that each opening is in communicationwith one of the other producing zones, and valve means associated witheach of said last-named openings for controlling ow therethrough.

5. An apparatus as set forth in claim 4, together with valve-actuatingmeans lowerable through each tubing string on a wire line forselectively opening and closing the valve means whereby each tubingstring may be selectively communicated with a desired producing zone.

6. An apparatus as set forth in claim 4, wherein one of the tubingstrings is formed with by-pass openings above and below the uppermostwell packer to establish communication between the tubing string and theannulus above and below the packer, a closure means removably mountedwith the tubing string to close said by-pass openings to direct flowupwardly through the tubing, and a cross-over unit adapted to besubstituted for said closure and having uid passage means to crossoverilow from the tubing to the annulus above the uppermost packer while atthe same time directing ilow from the annulus below said packer upwardlythrough the tubing.

7. An apparatus as set forth in claim 4, wherein one of the tubingstrings is formed with by-pass openings above and below the uppermostwell packer to establish communication between the tubing string and theannulus above and below the packer, a closure means removably mountedwith the tubing string to close said by-pass openings to direct flowupwardly through the tubing, and a cross-over unit adapted to besubstituted for said closure and having fluid passage means to crossoverflow from the tubing to the annulus above the uppermost packer while atthe same time directing iiow from the annulus below said packer upwardlythrough the tubing, said closure unit comprising an elongate tubularbody of a length sulicient to span the distance between the by-passopenings and having sealing means for sealing between the exterior ofthe body and the bore of the tubing.

8. An apparatus as set forth in claim 4, wherein one of the tubingstrings is formed with by-pass openings above and below the uppermostwell packer to establisll communication between the tubing string andthe anne-.lus above and below the packer, a closure means removablymounted with the tubing string to close said by-pass openings to directflow upwardly through the tubing, and a cross-over unit adapted to besubstituted for said closure and having iiuid passage means to crossoveriow from the tubing to the annulus above the 5 wire line.

References Cited in the file of this patent UNITED STATES PATENTS2,537,066 Lewis Jan. 9, 1951 2,790,50l Garrett et al Apr. 30, i9572,804,830 Garrett et al. Sept. 3, 1957 2,818,925 Garrett et a1. Jan. 7,1958 2,903,066 Brown Sept. 8, 1959

1. AN APPARATUS FOR SELECTIVELY PRODUCING FLUIDS FROM A PLURALITY OFFLUID PRODUCING ZONES INCLUDING, A PAIR OF PARALLEL TUBING STRINGSEXTENDING DOWNWARDLY WITHIN THE WELL BORE, A PLURALITY OF WELL PACKERSON SAID STRINGS AND POSITIONED BETWEEN THE PRODUCING ZONES WHEN THETUBING STRINGS ARE IN THE WELL BORE, WHEREBY SETTING OF THE WELL PACKERSSEPARATES SAID PRODUCING ZONES, NON-